Amino-functional silicone compounds

ABSTRACT

wherein R, R1, R16, R12, R13, R14 and R15 are selected from hydrogen and hydrocarbon radicals, while M is selected from sulfone and ketone groups, h is a whole number that varies from 2 to 20 and a is a whole number that varies from 0 to 2. This novel class of compounds are useful as flocculents for colloidal organic matter, as ingredients for detergent resistant polishes and as bonding agents for bonding various plastic resins and rubber to glass fibers and other types of glass material. A novel class of silicone compounds of the formula,

United States Patent 1 1 Berger 14 1 Sept. 2, 1975 1 AMINO-FUNCTIONALSILICONE COMPOUNDS [75] Inventor: Abe Berger. Schenectady. NY.

[73] Assignee: General Electric Company.

Waterford. NY.

[22] Filed: Oct. 23. 1973 [21] Appl. No.: 408.271

Related US. Application Data [63] Continuation of Ser. No. 174.165. Aug.23. 1971.

Pat. No. 3.801.572.

[52] U.S. Cl.. 260/243 R; 260/2918); 260/4482 B; 106/3; 252/184; 210/54[51] Int. CL" C071) 279/12; C071) 21 1/06 [58] Field 01 Search 260/243R. 293.9. 293.89

[56] References Cited UNITED STATES PATENTS 3,770,732 11/1973 Quinlan260/243 Primary E.\'aminer.|ohn M. Ford Attorney. Agent, or Firm-Donald.1. Voss. Esq.; E. Philip Koltos, Esq.; Frank L. Neuhauser. Esq,

[57] ABSTRACT A novel class of silicone compounds of the formula.

4 Claims. N0 Drawings AMINO-FUNCTIONAL SILICONE COMPOUNDS Thisapplication is a continuation of application Ser. No. 174,165, filedAug. 23, 1971, now US. Pat. No. 3,801,572.

BACKGROUND OF THE INVENTION The present invention relates to a novelclass of silicone compounds and. in particular, the present inven tionrelates to a novel class of silicone compounds having anamino-functional group attached to the silicon atom, where theamino-functional group has joined thereon a sulfone or ketone radical.

In various processes in industry, there are formed suspensions ofcolloidal matter in water and. ring h process. it is necessary toprecipitate this colloidal matter. In order to do this, variousflocculating agents are used. Presently, a great amount of research anddevelopment has been carried out in the purification of sewage and othertypes of water containing waste organic matter. During the purificationof this type of water. it is necessary to precipitate out of the watersuspended colloidal organic matter. Various flocculating agents havebeen used for such precipitation purposes with various amount ofsuccess. In particular, there are four types of floceulating atents,that is the colloidal hydroxides of polyvalent metals, anionic, nonionicand cationic polyeleetrolytes. Of these four classes of types offlocculating agents, the ones that have been found to be the mostefficient in flocculating suspended or colloidal organic matter havebeen cationic polyelcctrolytes.

Thus, present research is being carried out to find the most efficientpossible cationic polyelectrolytes useful in flocculating colloidalorganic matter.

In addition, silica sol or silicic acid has been used as a floceulatingagent for colloidal organic matter but this material was only of limitedefficieney. It is desirable to develop a novel composition which can bemixed with the silica sol for the purpose of forming a composition whichis very efficient in flocculating colloidal organic matter.

In an ever more increasing rate, glass type of materials, andparticularly glass fibers, are being used to form various manufactureditems, wherein the glass type of materials are bonded to varioussynthetic rubbers. as well as natural rubber, and also to differenttypes of plastic resins. In particular, it is desirable to utilize glassfibers, for instance in reinforcing rubber tires. and for other purposesso as to have a more durable article. For the production'of sucharticles. such as glass fiber reinforced tires, it was necessary todevelop bonding agents which would promote the bonding or adherence ofthe rubber or other plastic to the glass fiber or other type of glassmaterial. Such bonding agents have been developed. However, it isdesirable to produce novel compounds which will result in an evenstronger and more efficient bond between the glass fibers and the rubberor plastic resin.

As is well known, polishes are used to polish various types of itemsand, particular, various types of polishes are used for the purpose ofpolishing or improving the appearance of paint on automobiles. Sincesuch surfaces are exposed to strong detergents during washing. it isdesirable to mix into the polish an ingredient which will permit thepolished surface to resist the effect of strong detergents. Thus, thereis a desire for a detergent resistent ingredient for incorporation intopolishes of various types.

Thus. it is one object of the present invention to provide a novel classof silicone compounds.

' It is yet another object of the present invention to providea novelprocess for producing a novel class of silicone compounds.

It is still another object of the present invention to provide a novelclass of silicone compounds which are efficient flocculating agents inprecipitating organic colloidal matter from water.

It is yet another object of the present invention to provide a novelclass of silicone compounds which are useful in bonding glass types ofmaterials and particularly glass fibers to various rubbers and plasticresins.

It is an additional object of the present invention to provide a novelclass of silicone compounds which are useful as detergent resistantingredients in polishes.

These and other objects of the present invention are accomplished bymeans of the invention defined below.

SUMMARY OF THE INVENTION In accordance with the present invention. thereis provided a novel class of silicone compounds of the formula.

where R and R are selected from the class consisting of monovalenthydrocarbon radicals and halogenated monovalent hydrocarbon radicals. R,R, R", R and R are selected from the class consisting of hydrogen.

arlkyl radicals and aryl radicals of up to It) carbon atoms, M isselected from the class consisting of SO: and C=(), II is a whole numberthat varies from I to 20 and u is a whole number that varies from (1 to2.

Within the present invention there is also encompassed a novel class ofsilicone compounds of the formula.

where R, R, R, R, R. M. /1 and u are as defined previously. The radicalR" is selected from the class consisting of monovalent hydrocarbonradicals and halogenated monovalent hydrocarbon radicals. In the aboveformulas, it is desirable that the radicals R, R are methyl and R'", R,R R and R are hydrogen. It is also preferable that u be equal to 1).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT In formulas l and (2)above, the radicals R, R and R are selected from the class consisting ofmonovalent hydrocarbon radicals and halogenated monovalent hydrocarbonradicals, such as alkyl radicals, e.g., methyl. ethyl. propyl, butyl,octyl, etc. radicals; aryl radicals, e.g.. phenyl, naphthyl. tolyl,xylyl etc. radicals: aralkyl radicals, benzyl, phenylethyl, etc.radicals;

alkenyl radicals. e.g.. vinyl. allyl. cyclohexenyl. etc. radicals;cycloalkyl radicals. e.g.. eyclohexyl. cycloheptyl. etc. radicals;halogen-substitutcd monoyalent hy-- drocarbon radicals. such as. forexample. chlorophenyl. chloronaphthyl. dibromophenyl. etc. Preferably.the radicals R and R and R have no more than ll) carbon atoms. and morepreferably. the radicals R and R are alkyl radicals of l to 5 carbonatoms. such as methyl. ethyl. etc. The radical R is preferably an alkylradical or an alkenyl radical of IS carbon atoms or less. Morepreferably. the radical R" is methyl. ethyl. propyl. etc. The radicalsR. R'. R and R'. as well as R'. are independently selected from theclass consisting of hydrogen. alkyl radicals and aryl radicals.Preferably. these radicals are of l carbon atoms or less and. morepreferably. these radicals are hydrogen or lower alkyl radicals. such asmethyl. ethyl. propyl. butyl. etc. Within the scope of formulas l and(2). II is a whole number that varies from 1 to 20 and is preferably 10or less. The symbol a is a whole number that varies from to 2 and ispreferably 0. One of the more preferred compounds within the scope Offormula l has the formula.

IC.H.ol.siCH.CH.CH.rs so.

Preferred compounds coming within the scope Of both formula l andformula (2) are as follows:

| l rCH.O).,Si-CH.CH.CH. N-CH.CH.s-CH.

-Continued CH. H O l C.H.O).si CH. N CH.CH. s C.H.

OCH. H 0 C|C..H ,si CH.CH.CH.CH.CH.-r 1 cH.CH.s-CH. XH.

H H. CH. 0

l I l, iCH.O).siCH.CH.CH. N CH CH s cH.

The compound of formula l is produced by reacting a compound of theformula,

where the symbols R. R. R. R. R. R. R' and M and the whole numbers 11. uare as defined previously. The compounds of formulas 3 and (4) arepreferably reacted together in stoichiomctric proportions. Althoughexcesses of either compound may be used in the reaction. no advantage isgained by using such an excess. A solvent is not necessary in thereaction. although common inert hydrocarbon solvents may be used such asxylene. toluene. mineral spirits. benzene and cyclohexane. as well asthe common alkanol or ether solvents.

The reaction is preferably carried out at a temperature range of 50 to150C and. preferably. at a temperature range of 60 to 120C. A yield of70 to 90% is obtained at this temperature range if the reaction isallowed to proceed anywhere from 4 to 8 hours. No catalyst is necessaryin this reaction and the reaction proceeds without any difficulty at theelevated temperature range.

If desired. a basic catalyst may be used. such as sodium methoxide.Triton B. sodium amide. sodium hydroxide. trisodium phosphate. Rex-an201. tetrame thylethylenediamine. triethylphosphinc. triphenylphosphine.etc. It must be understood that such a basic catalyst is not necessary.In the event such catalyst is used. it should be used in the amount of0.5 to 5% by weight of the reactants of formulas (3) and (4). It isdesired that the acid type of catalyst not be used in this reactionsince they will react with the amine group of the compound of formula(3) and thereby form byproducts other than the desired product offormula l The compound of formula (2) above is formed by reacting thecompound of formula (3) with a compound of the formula.

1n the above formula (5 the radicals R. R. R and M are as previouslydefined. The reaction of the compounds of formula (3) with the compoundof formula (5 takes place under the same conditions and the same type ofcatalyst. although a catalyst is not necessary as described above withrespect to the reaction of the compounds of formulas (3) and (4). Inaddition. the yield obtained and the reaction between the compounds offormulas (3) and (5) to yield a compound of formula (2) is the same asthe previous reaction. The compound of formula (3) above is obtained byreacting a compound of the formula.

with a compound of the formula.

In formula (6) above. In is a whole number that varies from to 18. R andu are as previously defined. and Z is a halogen. preferably chlorine.The compounds of formulas (6) and (7) are well known compounds in theart and are readily available The compound of formula (7) ismanufactured by most commercial producers of silicone compounds. whilethe compound of formula 6) is sold commercially by Vistron. American Cyanamide (acrylonitrile). Aldrich. Robcrs. Kay Fries (allyl cyanide).etc. In the case where m is equal to 0. a catalyst system must be used.such as that defined in Bluestcin U.S. Pat. No. 2.971.970. Such acatalyst system may comprise. for instance. a mixture of tributy1amine=N.N.N-N-tetramethylethylenediamine and cuprous chloride. Thesecomponents may be present in equal proportions wherein the totalcatalyst mixture comprises from 1 to by weight of the two reactants offormula (6) and formula (7). This reaction may take place anywhere fromroom temperature and. preferably. in the range of 50 to 150C. Although asolvent is.

not necessary. any of the common inert hydrocarbon solvents may be used.The yield from this reaction is roughly. under the conditions specifiedabove and in the catalyst system specified above. from 60 to 80% in areaction period of 4 to 8 hours. For further details as to the abovereaction. one is referred to the above Bluestein patent whose disclosureis incorporated into this specification by reference.

lt should be noted that in place of the above Bluestein catalyst system.in the case where m is equal to 0 in formula (6). there may be usedother basic catalysts such as triphenylphosphine. dimethylformamide.tributylamine. and tricthylphosphine. Such catalysts may be used in aconcentration of l to 5% and. preferably. 1 to 3% by weight of the tworeactants of formulas (6) and (7). However. the catalyst systemparticularly in the Bluestein patent mentioned above. is preferred sincethe higher yields are obtained with that type of catalyst system in thereaction conditions disclosed therein.

In the case where m is equal to 1 and greater. then the reaction of thecompounds of formula (6) and formula (7) must take place in the presenceof a platinum catalyst.

The platinum compound catalyst can be selected from the group ofplatinum compound catalysts which are operative to catalyze the additionof siliconhydrogen bonds across olefinic bonds. Among the many usefulcatalysts for this addition reaction are chloroplatinic acid asdescribed in U.S. Pat. No. 2.823.218 Speier et al.. the reaction productof chloroplatinic acid with either an alcohol. an ether or an aldehydeas described in U.S. Pat. No. 3.220.972 Lamoreaux.trimethylplatinumiodide and hexamethyldiplatinum as described in U.S.Pat. No. 3.313.773 Lamoreaux. the platinum-olefin complex catalyst asdescribed in U.S. Pat. No. 3.159.601 Ashby and the platinum cyclopropanecomplex catalyst described in U.S. Pat. No. 3.159.662 Ashby. In thisplatinum catalyzed reaction. a solvent may or may not be used althoughthe solvent permits more intimate contact between the reactants. TheSiH-olefin addition reaction may be run at room temperature ortemperatures up to 200C. depending on catalyst concentration. Thecatalyst concentration can vary from 10 to 10 and. preferably. 10" to 10mole of platinum as metal per mole of olefinic-containing moleculespresent. Preferably. the reaction is run at a temperature range of to100C with the reactants dissolved in one of the common inert hydrocarbonsolvents. The reaction is allowed to proceed for 2 to.6 hours with ayield of the desired product being obtained of to %v The resultingproduct which still has halogen groups thereon. is

then taken and placed through an aleoholysis reaction. that is. thecompound is reacted with an alcohol such as ROH or an orthoformate suchas triethylorthoformate or trimethylorthoformate of the generic formula(R'O);.CH. where R is as defined previouslyand is preferably methyl orethyl. This type of reaction substitutes the halogen atoms attached tosilico with alkoxy and aryloxy groups. The reaction with the alcohol isthe well known type of alcoholysis reaction which is preferably carriedout in the temperature range of 50 to 120C. Preferably. a solvent is notused in the case where the orthoformate is used. However. when thealcohol is used. it is desirable to use a solvent such as xylene. ortoluene. in which the hydrogen chloride that is produced as a result ofthe reaction is not soluble. If a solvent is not used in thisalcoholysis reaction in which the hydrogen chloride byproduct is notsoluble. then a hydrogen chloride acceptor may be used as a solvent inthe reaction mixture so as to absorbthc HCl that is formed. An exampleof such a hydrogen chloride aeceptor is tributylamine.

Another way of removing the HCl that is formed in this alcoholysisreaction is to let the reaction proceed under vacuum. such as having avacuum of 20 mm of mercury or more. so as to remove the HCl that isformed. When the orthoformate is used. no HCl is formed and the HClacceptor is not necessary.

Asa. result of this alcoholysis reaction. there is obtained a product ofthe formula.

This compound of formula (8) can now be hydrogenated to change thenitrile group to an amine group. The compound of formula (8) is mixedwith hydrogen gas and. preferably. an excess of hydrogen gas is used toprovide sufficient pressure for the reaction to proceed at a desirablerate. It has been found convenient to employ the hydrogen reactant in anamount of from about 2 to about 20 chemical equivalents of the nitrilecompound of formula (8).

In the reaction there may be used inert hydrocarbon solvents or the wellknown alkanol solvents and the aromatic hydrocarbon solvents as. forexample. benzene. tolyene. etc. In addition. there is preferred as thecatalyst system. Raney nickel and Rancy cobalt. as well as certaineyclopentadienyl metals such as biscyclopentadienyl nickel. Thiscatalyst is preferably used in a concentration of 0.1 to by weight ofthe reactants, In addition to the nickel. there may be used ammonia fordirecting the reaction to the formation of principally primary amines.Thus. there may be used ammonia in the amount of about moles of ammoniaper mole of the nitrile compound so as to increase the yield of theprimary amine product. The reaction is preferably carried out attemperatures as low as 80C and at temperatures as high as 140C with goodresults. Temperatures. for example. below 80 and above 140C 'can beemployed. However. no advantage is obtained thereby. Although thereaction may be carried out at low pressures. such as 20 to 100 psig. itis preferable that the reaction be carried out at a pressure of 500 to l.000 psig. For more information as to this process and reaction. one, isreferred to U.S. Pat. No.

2.930.805". whose disclosure is incorporated into this specification byreference.

As a result of the hydrogenation of the compound of formula (8). thebasic reactant. that is the compound of formula (3) above. is obtained.The. other basic reactants. that is the compounds of formula (4) and formula (5) above. are compounds known in the art which are sold by suchcompanies as Aldrich Chemical Company. Madison. Wis. and Eastman. KodakCompany. Rochester. NY.

The compound of formula (4) may be synthesized by generally followingthe following synthesis procedure. In the first part of the synthesis.two compounds may be reacted in accordance with the following reaction:

The two reactants in reaction 1 above are well known in the art andcommercially sold by many manufacturing concerns. In reaction I above. acatalyst is not used. However. it is preferred that the reaction becarried out in the presence ofa common hydrocarbon solvent such asbenzene. toluene. xylene. as well as the ether solvents such astetrahydrofuran. Reaction 1 above is the Williamson ether-type ofsynthesis. The reaction proceeds to completion to result in a yield ofto 90% in a reaction time of 2 to 5 hours. Proceeding with thesynthesis. the reaction product of reaction I above is then taken andreacted with a peracid so as to oxidize the sulfur group to a sulfonegroup. This is a well known peracid oxidation. Examples of peracids thatcan be used are pcracetic acid. metachloroperbenzoic acid. perphthalicacid. methylethylketone peroxide. as-

well as other such types of acids. Preferably. 2 or more moles of theperacid is used per mole of the reaction product of reaction I above.The reaction may be carried out at a temperature range of 0 to 75C and.preferably. at a temperature range of 15 to 40C in a reaction time of 1to 4 hours to obtain a yield of 75 to The resulting sulfone product thatis obtained is then isolated from the peracetic acid after excessperacid id destroyed by distillation or other means and then taken anddissolved in one of the common inert hydrocarbon solvents or. morepreferably. a solvent such as dimethylformamide and particularly ethersolvents such as tetrahydrofuran. To the resulting solution there isthen added a basic reagent in a concentration of 2 molar equivalentsand. preferably. an excess of 25 molar per cent. The base used may beany type of basic dehydrohalogenation agents such as sodium hydroxide.sodium carbonate. a tertiary amine. any of the tertiary amines such astributylamine. l.5-diazobicyclo[430]non-5-ine. etc. In the presence ofsuch types of dehydrohalogenating agents and at a temperature rangingfrom 0'to 100C and preferably 15 to 40C. there is obtained from theresulting reaction the compound of formula (4). where .M'is equal to asulfone group. This reaction takes place in the preferred temperaturerange indicated above with a basic.dehydrohalogenating agent in 2 to 6hours with a yield of 80 to /1. Where M is equal to a ketone group informula (4), the compound is available from the manufacturers indicatedabove. One manner by which such a compound may be synthesized is by theinitial reaction of.

The two reactants indicated in reaction ll above are well knowncompounds which are commercially available. This reaction is preferablycarried out in the presence of .57 to 4% acid catalyst and. preferably.l to 2% by weight of the reactants. The acid catalyst may be selectedfrom many strong acids. such as hydrochloric. nitric and toluenesulfonic acids. This reaction is preferably carried out at roomtemperature but may be carried out at any temperature within the rangeof 20 to 100C. The reactants are preferably dissolved in one of thecommon inert hydrocarbon solvents or ether solvents. examples of whichhave been given above. The reaction may be carried out at reflux. thatis. at the reflux temperature of the solvent to continually azeotropeout the water that is formed during the reaction. The reaction productof reaction II above is then taken and chlorine gas is passed throughthe compound in the presence of ultraviolet rays which acts as acatalyst.

The reaction may be carried out at room temperature and. in fact. at anytemperature of from 20 to 100C. More preferably, the reaction is carriedout at a temperature range of 20 to 50C.

The reaction product of reaction ll above is prefera- 4 solvent. such astetrahydrofuran. The reaction may be carried out at any temperature inthe range of to 100C and is preferably carried out at l to 40C. Theconditions of the reaction are much the same type of reaction as usedpreviously in the synthesis of a compound of formula (4) wherein (4) isequal to a sulfone group. In other words. this is a dehydrohalogenationreaction in the presence of a dehydrohalogenating agent such as sodiumhydroxide, potassium hydroxide and the other basic catalysts disclosedabove.

The diolefin compound which is the reaction product of this reaction isobtained in a yield of to 80% in a reaction time of 2 to 6 hours. Thisdiolefin compound may then be taken and reacted with a catalytic amountof an acid such as acetic acid. sulfuric acid. toluene. sulfonic acid.etc.. in order to restore the ketone group in the compound. Thisacidification with one of the strong acids. some examples of which aregiven above,

10 takes place in the presence of water and any type of commonhydrocarbon solvent and. in particular. the common hydrocarbon solventsdisclosed above. Preferably. the reaction is carried out at the refluxtemperature of the solvent such as anywhere from 50 to 100C.

although the reaction may takeplace at an even higher temperature ifhigher boiling solvents are present. This reaction usually takes placeat the temperatures indicated in the time of l to 3 hours with yields ofto 8071.

The compounds within the scope of formula (5) are sold commercially bythe same companies as those that are indicated to sell commercially thecompounds of formula (4). In addition. it is obvious that such compoundswithin the scope of formula (5) may be produced by synthesis similar tothe ones indicated for producing the compounds within the scope offormula (4).

The following examples are given for the purpose of illustrating theinvention but are not intended to limit the scope of the invention inany way.

EXAMPLE 1 To a reaction mixture containing 44.2 gy-aminopropyltriethoxysilane (0.2 mole) there is added slowly 23.6 gdivinylsulfone (0.2 mole). A vigorous reaction occurs and the reactiontemperature rises to C. By controlling the rate of addition. thereaction is kept at 70- 10C. After complete addition. the reaction iskept at C for an additional 3 hours. A vapor phase chromatographyanalysis shows a high conversion to a high boiling adduct with verylittle starting material present. Upon fractionation. the productdistilled over at 186l 88C at 0.9 mm pressure and there is obtained 55 gof product. A vapor phase chromatographic analysis showed a purity ofabout 98% An infrared scan shows a sulfone absorption at 725p. and 8.6a.The absorption bands at 2.9;; and 6.3,u. present in the amine starting.material is absent in the: final product. The product has the formula.

EXAMPLE 2 To a reaction mixture containing a solution of 21.2 gmethylvinylsulfone in 50 parts of tetrahydrofuran is added dropwise at32C. 36 g y-aminopropyltrimethoxysilane. An exothermic reaction ensues.The reaction is run at 3245C by controlling rate of silane addition.Following complete addition. the reaction is heated to reflux at 68C andheld there for 4 hours. In examining the product by gas chromatography.a high boiling adduct is shown to be present. The product is distilledand isolated. lts identification is confirmed by infrared and nuclearmagnetic resonance spectroscopy and is in agreement with the formula of.

EXAMPLE 3 To a reaction mixture containing 19. 1 parts y-amino- Similarto the procedure shown in Example 1. the addition of l9.l partsaminomethyltriethoxysilane to 12.8 parts'divinylsulfone at ambienttemperature followed by a heating period at 70C for 2 hours forms theadduct.

,H -,());.Si(.H. .N

v (H. .-CH:

This product is'purified by distillation and its structure isconfirmedvby infrared and nuclear magnetic resonance spectroscopy.

EXAMPLE 5 The slow addition of Z-methyl.4-aminobutyldimethylethoxysilaneto an equimolar amount of phenylvinylsulfone dissolved intetrahydrofuran produces an exotherm. following which in accordance withconventional procedure can be isolated to a product of the followingstructure.

CH3 (I) This structure is confirmed by infrared and nuclear magneticresonance spectroscopy.

I claim:

l. A method for producing a silicone compound of the formula.

comprising reacting a compound of the formula.

with a compound of the formula.

where R and R are alkyl radicals of l to 5 carbon atoms. R. R'". R". Rand R areselected from the class consisting of hydrogen and alkylradicals of up to l() carbon atoms. M is selected from the classconsisting of S0 and I 11 is a whole number that varies from l to l0 anda is a whole number that varies from 0 to 2.

2. The method of claim 1 wherein thereactants are reacted in a l to 1mole ratio.

3. The method of claimtl wherein the reaction is maintained at atemperature of 60l2 0C. I

4. The method of claim 1 wherein the reaction takes 7 place in ahydrocarbon solvent selected from the class consisting of toluene,xylene. eyelohexane. mineral spirits and acetone.

1. A METHOD FOR PRODUCING A SILICONE COMPOUND OF THE FORMULA
 2. Themethod of claim 1 wherein the reactants are reacted in a 1 to 1 moleratio.
 3. The method of claim 1 wherein the reaction is maintained at atemperature of 60*-120*C.
 4. The method of claim 1 wherein the reactiontakes place in a hydrocarbon solvent selected from the class consistingof toluene, xylene, cyclohexane, mineral spirits and acetone.